<3 to milkybar if he's been rumbled.
The website wasn't automatically scraping, just a bunch of static links. I mirrored it here if anyone wants a look.
Purely guessing here, but I expect you'd need PartnerNet access and have a setup to log all of the url requests being sent from the console. They'd probably ban IP's pretty fast if you just brute force it.
If you actually look at the source for some of these, the images URLs are as follows:
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d80258410865/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d80258410861/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d80258410867/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d80258410868/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d80258410869/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d8025841086a/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d8025841086c/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d8025841086e/1033/boxartlg.jpg
http://download.xbox.com/content/images/66acd000-77fe-1000-9115-d802584112a1/1033/boxartlg.jpg
There's actually very little differerence in the URLs. If someone could sort out some sort of scraper that checks all URLs for artwork like that, you'd probably find some stuff that we haven't seen yet.